1. Field of the Invention
The present invention relates to a radiation imaging apparatus, a method for controlling the radiation imaging apparatus, and a non-transitory computer-readable storage medium.
2. Description of the Related Art
A radiation imaging apparatus performs an initializing operation that comprises periodically initializing each sensor of a sensor array and a readout operation that comprises reading out signals corresponding to the charges accumulated upon irradiation of radiation after the initializing operation. The apparatus performs the initializing operation to initialize charges due to the dark currents generated in the sensor array. If, however, radiation is irradiated during the initializing operation, signal components are lost by the initializing operation during this period.
According to Japanese Patent Laid-Open No. 2002-181942, it is possible to perform correction by using the signals stored by the initializing operation even if the signal output from each sensor by the initializing operation is temporarily stored in a frame memory and radiation is irradiated in the middle of initializing operation.
According to the method disclosed in Japanese Patent Laid-Open No. 2002-181942, in the initializing operation repeatedly performed until the start of readout operation, the signals obtained by signal reading operation are stored in a frame memory. It is therefore necessary to maintain a readout circuit for reading out signals and a processing unit for processing the signals in an active state. This leads to the consumption of power by the initializing operation even before the start of the radiation imaging. This makes it difficult to use a portable cassette-type radiation imaging apparatus for a long period of time.